Furthermore, a moderate to high level of CD19, CD5, CD44, CD31, CD55, CD82, CD62L, HLA-A, B, C, and HLA-DR expression and a low level of CD49c, CD21, and CD63 expression was observed in CLL-EVs, which could be used as biomarkers for CLL [204]. Here, CD19 is linked to B-cell chronic lymphocytic leukemia.